YACT: What the heck is wrong with my radiator? UPDATE X2: FIXED!!! Swapped out thermostat and all is good!

[yhelothar]

UPDATE Yep, turned out the thermostat was broken. It was stuck closed, and kept the coolant from freely entering the engine, which resulted in the pressure buildup in the radiator, and the engine overheating. Took me a while to swap it out as my corolla somehow doesn't have the thermostat housing at the top radiator hose, but rather at the bottom radiator hose. But after I finally figured that out, everything went smoothly. Engine temp guage now shows the needle at a bit below the middle now. No more overpressurizing and leaking! The head gasket is surprisingly fine too. Car is running smoothly.
Thanks for everyone's help!




You may have read my last thread about me driving with an empty radiator.
I've been trying to stop leaks in my radiator for 4 days already, and everytime I fix a leak, it leaks somewhere else.

First I replace the hose, which didn't do anything. Then I found out the neck of the tubing was cracked, so I use JB weld and sealed it. So all is good. And then I find out that it starts leaking at the other end of the tube. I figure I didn't screw the clamp tightly enough, which I couldn't because the only thing that would fit in that space was a butterknife. But I went over to my neighbor's house and borrowed a torque wrench that fitted, and I screwed it nice and tight. So the leaking stops there.

BUT NOW, it starts leaking at the resevior cap! It seems like the tube going into the cap is pumping in immense amounts of steam, which is causing the pressure in the resevior to build up, causing the cap to pop off from the pressure, and the water flows out through there.

It appears that the radiator leaking problem is a result of a high pressure build up, which explains why fixing one leak causes another leak. The leak was a relief for pressure, so fixing the leak will cause the pressure to rise again, and causing the next weakest link to fail.

It also appears that everything begins to go downhill once the water in the radiator reaches boiling point. I'd imagine that's when water starts turning to gas, and thus causing the pressure buildup.

So any ideas on how to fix it?

BTW, the headgasket seems to be fine again. I don't see any water in the oil, nor do I get steam coming out of the tailpipe. There is also no oil in the radiator water. I'm guessing the abundance of rust particles in the cooling system has sealed off any cracks.

Also thanks for all the advice you guys have given me in the past.

UPDATE:
OK, I tried using 50/50 antifreeze and water, and I did all the steps suggested to remove any air pockets. After, I went out to test it, and I drove about 0.3 miles when the temp guage went half way. At that point, I stopped and checked to see if anything was leaking and nothing was leaking. I turned around and headed home, and half way back, it begins overheating again. By the time I got home, the temp guage was almost hitting the red. The radiator was dripping pretty rapidly from the resevoir cap again.
I'm guessing the coolant is barely reaching the engine, and there is a clog somewhere in the system, keeping the coolant from reaching the engine, which explains why the engine overheats when there is still plenty of coolant in the radiator.

Can you guys give me an affirmation on my observations? So will swapping the radiator work if the water wasn't getting to the engine to begin with?

 

[imported_Tick]

Have you tried flushing the radiator?

 

[CrackRabbit]

cracked head/blown headgasket FTL.
Your car is toast.

 

[yhelothar]

Originally posted by: Tick
Have you tried flushing the radiator?

Are you supposed to leave the engine running while flushing the radiator?

 

[yhelothar]

Originally posted by: CrackRabbit
cracked head/blown headgasket FTL.
Your car is toast.

Why do you think my headgasket is toast? It seems to be keeping the coolant from entering the combustion chambers and motor oil.

 

[CrackRabbit]

Originally posted by: virtualgames0

Originally posted by: CrackRabbit
cracked head/blown headgasket FTL.
Your car is toast.

Why do you think my headgasket is toast? It seems to be keeping the coolant from entering the combustion chambers and motor oil.

The leak may be small enough that you don't notice the vapor coming out of your tailpipe but its enough to put air in your cooling system.
It will only get worse.
You basicaly have 2 choices, take it to a mechanic and have them check the head for warpage and cracks and have a new gasket put in or junk the car.

Edit: the leak may be just between the water jacket and a cylinder, that could be why you don't see chocolate milkshake oil or gunky stuff in your radiator.

 

[Frosty3799]

this is far-fetched, but you are letting the air bubbles out of the system before capping the radiator again right?

 

[Insane3D]

Here's a thought....have you considered getting a new radiator?

Oh, and CrackRabbit, you seem quite sure it's a cracked head/head gasket only reading that OP? Interesting...

Since when does a head gasket problem mean the car is junk? Even a cracked head?

 

[boomerang]

1) You may have an air pocket in the system. It sounds as if you lost a lot of coolant. Just filling the radiator back up is not going to cut it on most cars nowadays. You need to fill it with the engine running (from a cold start) and rev it up a little to get most of the air out and keep filling until it starts to overflow, and put that cap on quick. Then, check for air bleeds on the motor or hard hoses. These are at high points in the cooling system to allow trapped air to escape. You want to open them up untill coolant comes out and close them. You will need to top off the coolant in the radiator afterwards following the procedure above. PLEASE do not remove the radiator cap with a hot engine. If you have to wait for it to cool down before completing the job, do so.

2) It could be as simple as a stuck thermostat. The system is overheating and the coolant is boiling.

3) It could be a bad radiator cap. Cooling systems are kept under pressure to raise the boiling point of the coolant.

4) I keep mentioning coolant. You are talking about water. I hope you haven't filled the system with plain water. Water alone will boil well below a 50/50 mixture of water and antifreeze.

5) A lot of rust particles in the coolant? This is bad. Your system needs a flush badly. I would take it in for this. The pros can do a much better job of this than you or I will ever be able to do in our driveway. Especially in a neglected system. Modern engines are made of many metals. You may have a cast iron block with aluminum cylinder heads. Your radiator may be brass or aluminum and may have plastic side tanks. When you neglect a cooling system, acids build up the coolant that eat away at the metals. It also eats away at head gaskets. The coolants we use today also have rust inhibitors in them. If you have rust particles in the system. It has gone way too long between antifreeze changes. Get it flushed.

Hope some of this helps.

Edit: Oh, and JB Weld is not a permanent repair by any means. I'm not certain exactly where the cracked tubing is, but it sounds as if it's part of the radiator. That radiator needs to be repaired professionally or replaced.

 

[yhelothar]

Originally posted by: CrackRabbit

Originally posted by: virtualgames0

Originally posted by: CrackRabbit
cracked head/blown headgasket FTL.
Your car is toast.

Why do you think my headgasket is toast? It seems to be keeping the coolant from entering the combustion chambers and motor oil.

The leak may be small enough that you don't notice the vapor coming out of your tailpipe but its enough to put air in your cooling system.
It will only get worse.
You basicaly have 2 choices, take it to a mechanic and have them check the head for warpage and cracks and have a new gasket put in or junk the car.

Edit: the leak may be just between the water jacket and a cylinder, that could be why you don't see chocolate milkshake oil or gunky stuff in your radiator.

Sounds like a good explanation for the pressure buildup. I'll keep this in mind as one of the possibilities my cooling system is messed up.

 

[yhelothar]

Originally posted by: Insane3D
Here's a thought....have you considered getting a new radiator?

Oh, and CrackRabbit, you seem quite sure it's a cracked head/head gasket only reading that OP? Interesting...

Since when does a head gasket problem mean the car is junk? Even a cracked head?

Yeah I've actually called my mechanic, and he suggested me to get a new radiator. He said he can get it swapped out for $200. I think I'm going to go for that if I can't get it fixed on my own. I really want to save money here as this car isn't worth too much to begin with. This is why this car is junk to me if the head gasket is broken. It's just not worth it for this car to spend the money to fix the head gasket.

 

[Insane3D]

Ahh...well a radiator switch is easy to do...you can do it yourself. If they are charging you $200, the radiator is probably $100 or less.

 

[fbrdphreak]

Originally posted by: boomerang
1) You may have an air pocket in the system. It sounds as if you lost a lot of coolant. Just filling the radiator back up is not going to cut it on most cars nowadays. You need to fill it with the engine running (from a cold start) and rev it up a little to get most of the air out and keep filling until it starts to overflow, and put that cap on quick. Then, check for air bleeds on the motor or hard hoses. These are at high points in the cooling system to allow trapped air to escape. You want to open them up untill coolant comes out and close them. You will need to top off the coolant in the radiator afterwards following the procedure above. PLEASE do not remove the radiator cap with a hot engine. If you have to wait for it to cool down before completing the job, do so.

2) It could be as simple as a stuck thermostat. The system is overheating and the coolant is boiling.

3) It could be a bad radiator cap. Cooling systems are kept under pressure to raise the boiling point of the coolant.

4) I keep mentioning coolant. You are talking about water. I hope you haven't filled the system with plain water. Water alone will boil well below a 50/50 mixture of water and antifreeze.

5) A lot of rust particles in the coolant? This is bad. Your system needs a flush badly. I would take it in for this. The pros can do a much better job of this than you or I will ever be able to do in our driveway. Especially in a neglected system. Modern engines are made of many metals. You may have a cast iron block with aluminum cylinder heads. Your radiator may be brass or aluminum and may have plastic side tanks. When you neglect a cooling system, acids build up the coolant that eat away at the metals. It also eats away at head gaskets. The coolants we use today also have rust inhibitors in them. If you have rust particles in the system. It has gone way too long between antifreeze changes. Get it flushed.

Hope some of this helps.

Edit: Oh, and JB Weld is not a permanent repair by any means. I'm not certain exactly where the cracked tubing is, but it sounds as if it's part of the radiator. That radiator needs to be repaired professionally or replaced.

The man speaks the truth. It could be any number of small issues. If you can't isolate the issue yourself; take it in, explain the issues and what you've done, they can probably isolate the specific problem pretty quickly and go from there. Do it now before it gets worse.

 

[boomerang]

Have your mechanic pressure test the system. He'll be able to tell right away where the leaks(s) are. He should also have some test strips he can use to tell if there are combustion gases in the coolant. A sure sign of a cylinder head, head gasket or manifold leak or crack.

 

[CrackRabbit]

Originally posted by: Insane3D
Here's a thought....have you considered getting a new radiator?

Oh, and CrackRabbit, you seem quite sure it's a cracked head/head gasket only reading that OP? Interesting...

Since when does a head gasket problem mean the car is junk? Even a cracked head?

The reason i think its a cracked head or blown gasket is because he ran his car without water for an extended period of time, read his old thread on the matter.
Its a 1991 Toyota Corolla, if it is a blown gasket or cracked head (I would certianly be very happy for the OP if I was wrong) you have to weigh if the cost of doing the repairs, especialy in the case of a cracked head vs the value of the car.

 

[sao123]

Flush the system && Replace the radiator... FTW.
radiators clog up and give undue pressure which cause system wide leaks.

 

[yhelothar]

Originally posted by: boomerang
1) You may have an air pocket in the system. It sounds as if you lost a lot of coolant. Just filling the radiator back up is not going to cut it on most cars nowadays. You need to fill it with the engine running (from a cold start) and rev it up a little to get most of the air out and keep filling until it starts to overflow, and put that cap on quick. Then, check for air bleeds on the motor or hard hoses. These are at high points in the cooling system to allow trapped air to escape. You want to open them up untill coolant comes out and close them. You will need to top off the coolant in the radiator afterwards following the procedure above. PLEASE do not remove the radiator cap with a hot engine. If you have to wait for it to cool down before completing the job, do so.

2) It could be as simple as a stuck thermostat. The system is overheating and the coolant is boiling.

3) It could be a bad radiator cap. Cooling systems are kept under pressure to raise the boiling point of the coolant.

4) I keep mentioning coolant. You are talking about water. I hope you haven't filled the system with plain water. Water alone will boil well below a 50/50 mixture of water and antifreeze.

5) A lot of rust particles in the coolant? This is bad. Your system needs a flush badly. I would take it in for this. The pros can do a much better job of this than you or I will ever be able to do in our driveway. Especially in a neglected system. Modern engines are made of many metals. You may have a cast iron block with aluminum cylinder heads. Your radiator may be brass or aluminum and may have plastic side tanks. When you neglect a cooling system, acids build up the coolant that eat away at the metals. It also eats away at head gaskets. The coolants we use today also have rust inhibitors in them. If you have rust particles in the system. It has gone way too long between antifreeze changes. Get it flushed.

Hope some of this helps.

Edit: Oh, and JB Weld is not a permanent repair by any means. I'm not certain exactly where the cracked tubing is, but it sounds as if it's part of the radiator. That radiator needs to be repaired professionally or replaced.

Thanks for the advice.
1. Yeah I didn't try starting the engine and revving it a bit when filling the radiator. Would that have actually made a difference though? So basically you're saying the high water pressure in the radiator caused by the lack of air, would raise the boiling point of the water, and thus ultimately reducing pressure by preventing steam?

3. What are indicators of a broken radiator cap?

4. Yeah I've been using plain water until I can get it to not leak. Is the water causing my radiator to fail? I've thought about it. The coolant bottle says the boiling point is risen to 265°F, compared to 212°F of water. So is 50F enough to make a difference?

And about the JB Weld. It was suggested to me by people on ATOT. It seems to hold the leak well. I don't need it to last a few years. Just a few more weeks until I can get another car. If it can do that, I'm fine with it.

 

[IGBT]

..you can spend a lot of time and money trying to patch a shot radiator. Better off exchanging it for a re-core/rebuild and do the job once and be done wit it.

 

[yhelothar]

I tried flushing the system with the engine on to see if water was getting to the engine.
The temp while flushing was in the center of the guage. Is that normal?

 

[Black88GTA]

A bad radiator cap will cause overpressure of the system. If the system was designed for, say, 15 lbs of pressure, a good cap will open at that pressure and vent to the overflow tank. If the spring in the cap is stuck or bad, it may no longer be opening at 15 lbs, causing higher system pressure and increasing the potential for leaks. If it's the original cap, it should be replaced anyways as a matter of preventative maintenance. It's only a couple bucks for a new one.

A thermostat would be a good idea too - again, only a couple bucks and usually fairly easy to replace.

A new radiator for your car is $108 from Autozone. If the mechanic only wants $200 to swap it out, I'd bet it's a really simple job on your car. You could probably do it yourself in an hour or two. I once did a radiator swap in my apartment building's parking lot. Sounds like a new radiator, cap, and thermostat, plus a good cooling system flush, would do wonders for it.

 

[yhelothar]

Originally posted by: IGBT
..you can spend a lot of time and money trying to patch a shot radiator. Better off exchanging it for a re-core/rebuild and do the job once and be done wit it.

Yeah the thing is.. if I would've known it would take so much time and money before fixing the first simple leak, then yeah, of course I would've just exchanged the radiator.

 

[yhelothar]

Originally posted by: Black88GTA
A bad radiator cap will cause overpressure of the system. If the system was designed for, say, 15 lbs of pressure, a good cap will open at that pressure and vent to the overflow tank. If the spring in the cap is stuck or bad, it may no longer be opening at 15 lbs, causing higher system pressure and increasing the potential for leaks. If it's the original cap, it should be replaced anyways as a matter of preventative maintenance. It's only a couple bucks for a new one.

A thermostat would be a good idea too - again, only a couple bucks and usually fairly easy to replace.

A new radiator for your car is $108 from Autozone. If the mechanic only wants $200 to swap it out, I'd bet it's a really simple job on your car. You could probably do it yourself in an hour or two. I once did a radiator swap in my apartment building's parking lot. Sounds like a new radiator, cap, and thermostat, plus a good cooling system flush, would do wonders for it.

Thanks.. I'll try the first two first.

 

[yhelothar]

UPDATE:
OK, I tried using 50/50 antifreeze and water, and I did all the steps suggested to remove any air pockets. After, I went out to test it, and I drove about 0.3 miles when the temp guage went half way. At that point, I stopped and checked to see if anything was leaking and nothing was leaking. I turned around and headed home, and half way back, it begins overheating again. By the time I got home, the temp guage was almost hitting the red. The radiator was dripping pretty rapidly from the resevoir cap again.
I'm guessing the coolant is barely reaching the engine, and there is a clog somewhere in the system, keeping the coolant from reaching the engine, which explains why the engine overheats when there is still plenty of coolant in the radiator.

Can you guys give me an affirmation on my observations? So will swapping the radiator work if the water wasn't getting to the engine to begin with?

 

[yhelothar]

Anyone?

 

[mwtgg]

This thread would get nasty if he owned an American car.